Evolution Not Random

[articulett]

You're saying mutations aren't random?! Wow...that's...wow. I don't even know where to begin. Those "causes" are interactions that can only be described by quantum mechanics. Nothing is more random that that. Nothing.

I was a genetic counselor, and this is a little hairy-- [FONT=Verdana, Arial, Helvetica, sans-serif]although the adjective frequently applied to the process of "mutation" is "random", the probability of genetic change is not identical for every nucleotide in a genome. DNA sequence affects DNA structure. There are hot spots for crossing over and methylation and places that are highly conserved and very resistant to mutation. Moreover, although it appears to us that mistakes just happen--that does not mean there is not a physical reason for the copying errors (radiation for example--older eggs and sperm have more point mutations and nondisjunction of chromosomes.)

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[/FONT] Random:
unpredictable in some way. Mutations are “random” in the sense that the sort of mutation that occurs cannot generally be predicted based upon the needs of the organism. However, this does not imply that all mutations are equally likely to occur or that mutations happen without any physical cause. Indeed, some regions of the genome are more likely to sustain mutations than others, and various physical causes (e.g., radiation) are known to cause particular types of mutations.

http://evolution.berkeley.edu/evosite/glossary/glossary_browse.shtml

[FONT=Verdana, Arial, Helvetica, sans-serif]
That is why peer reviewed scientists are very careful to describe what their terms mean, and none would ever use random the way Mijo does.

http://www.pnas.org/cgi/content/full/104/suppl_1/8567

[/FONT] Chance is, nevertheless, an integral part of the evolutionary process. The mutations that yield the hereditary variations available to naturalselection arise at random. Mutations are random or chance events because ( i) they are rare exceptions to the fidelity of the process of DNA replication and because (ii) there is no way of knowing which gene will mutate in a particular cell or in a particular individual. However, the meaning of "random" that is most significant for understanding the evolutionary process is (iii) that mutations are unoriented with respect to adaptation; they occur independently of whether or not they are beneficial or harmful to the organisms. Some are beneficial, most are not, and only the beneficial ones become incorporated in the organisms through natural selection.

 

[andyandy]

just popping in to see how the thread's going....
good to see the same one word semantic tussle still kicking on - bets on 1000 posts?


while i'm here....what's a "genetic counselor"? I've never heard of the term in the uk.....

 

[mijopaalmc]

what's a "genetic counselor"?

Someone who counsels people of the genetic risks of having children, such as what the probability of a the person's child having cystic fibrosis.

 

[andyandy]

Someone who counsels people of the genetic risks of having children, such as what the probability of a the person's child having cystic fibrosis.

cheers - i think that advice is covered by doctors over here....

well at least i've learnt something new from the thread

 

[Jorghnassen]

just popping in to see how the thread's going....
good to see the same one word semantic tussle still kicking on - bets on 1000 posts?

We haven't reached 500 posts of sodomizing flies yet. I say it'll reach at least 750 posts of pointless bickering, but I wouldn't bet on 1000 yet.

 

[mijopaalmc]

We haven't reached 500 posts of sodomizing flies yet. I say it'll reach at least 750 posts of pointless bickering, but I wouldn't bet on 1000 yet.

Actually, I think that the "original" thread is over 2500 posts long. I really should have resisted posting in this one, because articulett didn't really want to discuss the issue. She meant the OP purely as bait for those who disagreed with her, and, as you can tell, she is certainly the master baiter.

 

[Meadmaker]

Not even the random die being quantum mechanically rolled in the opponent's head?

That's exactly correct, i.e. to point out that random events do in fact influence a game of chess.

Again, it all depends on the aspect you are looking at. Saying "Chess is random" and "Chess is non-random" are equally wrong.

 

[Meadmaker]

While I continue to avoid the tax prep that I really should be using my computer for, a further thought. The whole two component view of things (i.e. mutation =random, selection = non-random) view of things was probably created before mutation was known, in terms of DNA modification, and selection was not studied in great detail.

Was it first proposed by Darwin himself? At any rate, before the mechanisms were known, someone somewhere said that there was random variation (mutation), and non-random selection, as a way of describing first how change happens, and then how change becomes part of a species.

Does it have real explanatory power? Sure, it does. It's simple, and covers the basics. Of course, dogmatic insistence that it is the only worthwhile explanation at any level doesn't work so well. When you start asking, "Yes, but 'how' does the selection occur," you have to end up with probabilistic (i.e. random) descriptions.

 

[mijopaalmc]

Can genetic polymorphisms (e.g., the HbS mutation or the numbers of CAG repeats in Huntingtin) be know with absolute certainty?

 

[Skeptic Ginger]

While I continue to avoid the tax prep that I really should be using my computer for, a further thought. The whole two component view of things (i.e. mutation =random, selection = non-random) view of things was probably created before mutation was known, in terms of DNA modification, and selection was not studied in great detail.

Was it first proposed by Darwin himself? At any rate, before the mechanisms were known, someone somewhere said that there was random variation (mutation), and non-random selection, as a way of describing first how change happens, and then how change becomes part of a species.

Does it have real explanatory power? Sure, it does. It's simple, and covers the basics. Of course, dogmatic insistence that it is the only worthwhile explanation at any level doesn't work so well. When you start asking, "Yes, but 'how' does the selection occur," you have to end up with probabilistic (i.e. random) descriptions.

The only thing I would add to this are the more recent discoveries that much of the supposed random mutations are not quite as random as first thought. Evolution would of course had to have been random initially. But something else to consider here is that natural selection selects variability. Then given more time, controlling those mutations has an advantage so mutation control mechanisms are selected.

Then if you wanted to get even more speculative, (though still evidence based) natural selection selected organisms which exerted control over the direction of evolution of other organisms. And now natural selection has selected organisms that are in the early stages of beginning to very specifically control their own evolution. So natural selection moves the organisms toward less and less randomness. Again, not ideology, it is what the evidence reveals.

 

[cyborg]

That's exactly correct, i.e. to point out that random events do in fact influence a game of chess.

Again, it all depends on the aspect you are looking at. Saying "Chess is random" and "Chess is non-random" are equally wrong.

So, are we finally at a point where we can agree where describing the qualities of a process by the qualities of its inputs doesn't make sense?

 

[mijopaalmc]

The only thing I would add to this are the more recent discoveries that much of the supposed random mutations are not quite as random as first thought. Evolution would of course had to have been random initially. But something else to consider here is that natural selection selects variability. Then given more time, controlling those mutations has an advantage so mutation control mechanisms are selected.

Then if you wanted to get even more speculative, (though still evidence based) natural selection selected organisms which exerted control over the direction of evolution of other organisms. And now natural selection has selected organisms that are in the early stages of beginning to very specifically control their own evolution. So natural selection moves the organisms toward less and less randomness. Again, not ideology, it is what the evidence reveals.

You know very well that most of the problem in these discussions stems from the stubborn refusal on the part of those who insist that evolution is non-random to accept the perfectly valid and well- and widely-accepted definition of "random" as "[o]f or relating to a type of circumstance or event that is described by a probability distribution", which describes a situation in which there is strictly more than one outcome for identical initial conditions. Instead, they continue to construct the same, old, tired straw man that the above definition "makes everything random". Yes, mutation and natural selection have causes, constraints, direction, and are most likely not evenly distributed over the genome of an individual or the individuals of a population, but that has no effect of the the designation of evolution by natural selection as "random" or "stochastic", by the above definition. Until those who insist evolution is non-random realize this and correct their argument accordingly, it will be fallacious as far refuting what jimbob, Meadmaker, Walter Wayne, and I have said about evolution being probabilistic, random, or stochastic, as the entire argument that evolution is non-random because mutation and natural selection mutation and natural selection have causes, constraints, direction, and are most likely not evenly distributed over the genome of an individual or the individuals of a population is as described above* is based on equivocation.

*i.e., mutation and natural selection have causes, constraints, direction, and are most likely not evenly distributed over the genome of an individual or the individuals of a population

 

[Fredrik]

the perfectly valid and well- and widely-accepted definition of "random" as "[o]f or relating to a type of circumstance or event that is described by a probability distribution", which describes a situation in which there is strictly more than one outcome for identical initial conditions. Instead, they continue to construct the same, old, tired straw man that the above definition "makes everything random".

That definition does make everything random, but I think you could change it a bit to make it more useful. You could say explicitly that it applies to theories, i.e. to descriptions of things that happen in the universe, rather than to actual things in the universe.

According to your definition, a system consisting of 3 particles that interact gravitationally is random. A small change in the initial conditions can give us a very different result. See e.g. this page. In the real world, quantum mechanical processes (e.g. the decay of a single uranium atom) can be enough to change the initial conditions enough. In the theory however, i.e. in the classical theory used to describe this system, there are no quantum effects, and no randomness. The theory is deterministic.

Compare this to evolution, where randomness is an integral part of the theory itself, and not just a real-world complication.

 

[Meadmaker]

So natural selection moves the organisms toward less and less randomness. Again, not ideology, it is what the evidence reveals.

The organisms aren't very random at all. That's the cool thing about evolution. It's an example of how a bunch of random events can end up with a very predictable, stable, outcome. Order out of chaos, and all without a director.

 

[sol invictus]

You know very well that most of the problem in these discussions stems from the stubborn refusal on the part of those who insist that evolution is non-random to accept the perfectly valid and well- and widely-accepted definition of "random" as "[o]f or relating to a type of circumstance or event that is described by a probability distribution", which describes a situation in which there is strictly more than one outcome for identical initial conditions. Instead, they continue to construct the same, old, tired straw man that the above definition "makes everything random".

Strawman??

Please provide one single example of a physical process (not a mathematical abstraction) which is not random by your definition.

Until you do so (and you cannot), no one will take it seriously.

 

[mijopaalmc]

That definition does make everything random, but I think you could change it a bit to make it more useful. You could say explicitly that it applies to theories, i.e. to descriptions of things that happen in the universe, rather than to actual things in the universe.

According to your definition, a system consisting of 3 particles that interact gravitationally is random. A small change in the initial conditions can give us a very different result. See e.g. this page. In the real world, quantum mechanical processes (e.g. the decay of a single uranium atom) can be enough to change the initial conditions enough. In the theory however, i.e. in the classical theory used to describe this system, there are no quantum effects, and no randomness. The theory is deterministic.

Compare this to evolution, where randomness is an integral part of the theory itself, and not just a real-world complication.

Strawman??

Please provide one single example of a physical process (not a mathematical abstraction) which is not random by your definition.

Until you do so (and you cannot), no one will take it seriously.

It seems that people are having a hard time understanding the difference between a chaotic systems and random (or stochastic) systems. In a chaotic system identical initial conditions lead to identical final conditions. In other words, chaotic systems are deterministic, and it is only through small differences in initial conditions and large differences in final conditions result. In random systems, identical initial conditions can lead to different final conditions result. These definitions make a testable claim about evolution (i.e., organisms with identical "initial conditions" will always have identical "final conditions" if the system is chaotic, where as the organisms with identical "initial conditions" will have different "final conditions", in some measurable way if the system is random (or stochastic)). Unfortunately, this also presents a problem, namely how to define the "initial conditions" and "final condition", but I think that is a subject for either another post or another thread.

 

[sol invictus]

It seems that people are having a hard time understanding the difference between a chaotic systems and random (or stochastic) systems.

Still avoiding answering my simple question?

Please give one example of a physical process that is not random by your definition.

 

[Fredrik]

It seems that people are having a hard time understanding the difference between a chaotic systems and random (or stochastic) systems.
...

I'm sure that there are people who don't understand that difference, but Sol Invictus and I do understand it (and I believe our posts in this thread show it). You're missing the point. A real-world physical system that we would describe with a classical theory is not deterministic just because the theory is. All real-world physical systems are random according to your definition. That's why I suggested that you change it.

 

[Tumbleweed]

Once upon a time there were pink,green, blue, and yellow snow shoe hares, as well as white ones. For many years they enjoyed an arctic paradise until Mother Nature and her Terminator Natural Selection sent a buch of predators to live among them. Since all the pink, green, blue, and yellow snow shoe hares stood out like a sore thumb in the snow, they got gobbled up. The white ones were invisible to the predators and so they lived to procreate another day.
And that, to those who have a very simple grasp of logic is how evolution works and why it is not random
My theory is quite the opposite: The snowshoe hare on some level knows that if it does not use camoflauge as a device againt predators, it will become extinct,.
Therefore, it deliberately manipulates its own DNA to provide it with a white coat in winter
And consider this if you do not think that cells have a form of consciousness: when was it infused in you? When you were born? As a 3 month old fetus? Or as a zygote. Are we nothing more than a colletion of cells? If so, then cells must have consciousness

 

[kjkent1]

It seems that people are having a hard time understanding the difference between a chaotic systems and random (or stochastic) systems. In a chaotic system identical initial conditions lead to identical final conditions. In other words, chaotic systems are deterministic, and it is only through small differences in initial conditions and large differences in final conditions result. In random systems, identical initial conditions can lead to different final conditions result. These definitions make a testable claim about evolution (i.e., organisms with identical "initial conditions" will always have identical "final conditions" if the system is chaotic, where as the organisms with identical "initial conditions" will have different "final conditions", in some measurable way if the system is random (or stochastic)). Unfortunately, this also presents a problem, namely how to define the "initial conditions" and "final condition", but I think that is a subject for either another post or another thread.

What you seem to be missing is that as related to real-world systems, there is no system which maintains an identical initial state over multiple trials; therefore by your definition of terms, no system is deterministic. This renders any discussion of determinism vs. stochastic-ism meaningless except as a mathematical abstraction.